<p> Recently, a new trend called cold brewing gained the popularity in the tea and coffee beverage industry. Cold brew and hot brew black tea may have different sensory qualities and antioxidant levels because of their polyphenolic properties and brewing process. The objectives of this study were to determine antioxidant properties and the polyphenolic content of commercial brands of cold brew and hot brew black tea. The total phenolics content of the cold brew tea was determined to be 0.19 mg/mL gallic acid equivalents/100 g and hot brew tea was 0.43 mg/mL gallic acid equivalents/100 g when assayed by Folin-Ciocalteu’s reagent method. The total flavonoids content of the cold brew tea was 0.40 mg/mL catechin equivalents/100 g and hot brew was 1.01 mg/mL catechin equivalents/100 g. Moreover, antioxidant capacity of cold brew and hot brew black tea were analyzed where their ability to scavenge DPPH radicals were 86.3% and 88.1% respectively. There was a significant difference in total phenolics content between cold brew and hot brew (<i>p</i> = 0.004). Similarly, there was a significant difference in total flavonoids between cold brew and hot brew (<i>p</i> = 0.004). Additionally, there was a significant difference in DPPH scavenging activity between cold brew and hot brew (<i>p</i> = 0.016). Overall, it can be concluded that although cold brew tea contained a lower amount of phenolics and flavonoids as compared to hot brew tea, they both were able to scavenge DPPH radicals in nearly same capacity.</p><p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:10977486 |
| Date | 25 April 2019 |
| Creators | Magammana, Chathuranga Manhari |
| Publisher | California State University, Long Beach |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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